Hand Compartment Syndrome

Compartment syndrome is defined by high pressures in a closed myofascial compartment, which affects initially the muscles and later the nerves and vessels. The hand is rarely affected, but if treated suboptimally, it results to a permanent loss of function. Eleven compartments are included in the hand and wrist. Diagnosis of compartment syndrome of the hand remains challenging. Pain out of proportion of injury and excessive swelling should raise suspicion towards a compartment syndrome. Intracompartmental pressure measurement contributes to the diagnosis, but it is not always reliable. Once the diagnosis of acute compartment syndrome has been made, decompression of all compartments is mandatory, in order to achieve a good outcome. Failing to manage this emergent condition properly leads to a significant hand disability. Our chapter includes the following sections: 1. Introduction. A brief description of the hand compartment syndrome is presented. 2. Anatomy. Special considerations regarding hand compartments are presented, 3. Etiology. 4. Diagnosis. Signs and symptoms are reported, as well as guidelines of the technique of intracompartmental pressure measurement. 5. Treatment. Faciotomies’ indications and operative technique are described in details. 6. Conclusion. Appropriate figures of the clinical image and surgical decompression are presented as well

Concordancia entre el decir y el hacer

La autora hace un inteligente planteamiento de la crisis social como repercusión del desplazamiento a la nueva economía mundial. Abre el panorama de los escenarios posibles, sin descuidar el aspecto laboral, tan poco atendido en los tiempos actuales

Achievable QoS in a Shared Wireless Channel

In this work, call admission and transmission scheduling policies are studied for a TDMA system servicing Variable Bit Rate (VBR) applications with distinct QoS requirements and traffic characteristics. In this environment, packets which experience excess delays are dropped (due to delay violations) at the source. In addition, packets are dropped at the receiver due to channel induced errors (interference) in the wireless link. The focus of the research is to determine the region of achievable QoS vectors for heterogeneous VBR applications in this shared resource environment and study the impact that channel quality has on the achievable performance. The region of achievable QoS vectors is central to the call admission problem and in this work, it is used to identify a class of scheduling policies capable of delivering any achievable performance

Determining the Call Admission Region for Real-Time Heterogeneous Applications in Wireless TDMA Networks

The call admission problem for a wireless packet switched network supporting homogeneous applications - such as a cellular voice network - is an old one and has been extensively investigated in the past. The focus of the present article is to investigate the call admission region for a TDMA (wireless) system supporting heterogeneous real-time variable bit rate (VBR) applications with distinct quality of service (QoS) requirements and traffic characteristics. The QoS is defined in terms of a maximum tolerable packet delay and dropping probability; packets may be dropped due to delay violations or channel induced errors. The call acceptance region is investigated in this article under the assumption that each user's per frame resource (slot) requests are communicated to the scheduler (resource allocation authority). The call acceptance region is shaped by the QoS that can be delivered by the up-link scheduling policy. In the beginning of this article, some mechanisms employed to inform ..

Delivering QoS Requirements to Traffic with Diverse Delay Tolerances in a TDMA Environment

In Wireless ATM networks transmission resources are shared among geographically disperse applications with diverse Quality of Service (QoS) requirements and traffic characteristics. To provide QoS guarantees and use the bandwidth efficiently, call admission and scheduling functions are necessary. These functions should ensure the delivery of the target QoS to the supported applications while achieving statistical multiplexing gains, without explicit and continuous exchange of information between sources and scheduler. In this paper the problem of sharing resources (slots of an up-link TDMA frame) among heterogeneous Variable Bit Rate (VBR) applications with diverse QoS requirements is addressed. The QoS requirements for each application is defined in terms of a maximum tolerable packet delay and dropping probability; a packet is dropped if it experiences excess delay. The region of achievable QoS vectors is established for policies that are work-conserving and satisfy the earliest due..

Delivering QoS requirements to traffic with diverse delay tolerances in a TDMA environment

Abstract — The focus of this paper is on determining the call admission region and scheduling policies for a time-division multiple-access (wireless) system supporting heterogeneous realtime variable bit rate applications with distinct quality of service (QoS) requirements and traffic characteristics. The QoS is defined in terms of a maximum tolerable packet delay and dropping probability. A packet is dropped if it experiences excess delay. The call admission region is established for policies that are workconserving (WC) and that satisfy the earliest due date (EDD) service criterion (WC-EDD policies). Such policies are known to optimize the overall system performance. In addition to the determination of the call admission region, this study leads also to the construction of scheduling policies that deliver any performance in the region established for WC-EDD policies. Finally, an upper bound on the call admission region that can be achieved under any policy (not limited to the WC-EDD policies) is determined. Index Terms — Integrated services, QoS, scheduling, TDMA, wireless

Achievable QoS in an Interference/Resource Limited Share Wireless Channel

Abstract — In this work, the region of achievable quality-ofservice (QoS) is precisely described for a system of real-time heterogeneous variable bit rate (VBR) sources competing for slots (packet transmission times) of a time division multiple access (TDMA) frame. The QoS for each application is defined in terms of a maximum tolerable packet-dropping probability. Packets may be dropped due to delay violations and channel induced errors. The region of achievable QoS is precisely described for an interference/resource limited network by considering the underlying TDMA-multiple access control (TDMA-MAC) structure and the physical channel. A simple QoS-sensitive errorcontrol protocol that combats the effects of the wireless channel while satisfying the real-time requirements is proposed and its impact on the region of achievable QoS is evaluated. The results presented here clearly illustrate the negative impact of a poor channel and the positive impact of the employed error-control protocol on the achievable QoS. The region of achievable QoS vectors is central to the call admission problem, and in this work, it is used to identify a class of scheduling policies capable of delivering any achievable performance. Index Terms — Achievable quality-of-service (QoS), integrated services, wireless resource